Working platform

ABSTRACT

Working platforms for scaffolding must be light and functional and easily stackable. It must therefore be possible to include all their components with a long useful life in the static calculations as well. The requirements include both great rigidity in the corner joint of a rectangular bearing frame for the working platform and the smallest possible gaps between adjacent platforms. Above all, however, the smallest possible number of components must be used to keep the costs of such a working platform within limits. To this end the invention makes use of a U-shaped folded footplate (2) clamped between the longitudinal bearing members (11) of the bearing frame. If, in addition, at least the longitudinal bearing members (11) are rectangular hollow sections, no dirt or residual building material can enter the working platform.

FIELD OF THE INVENTION

The invention relates to a working platform for a scaffolding or thelike, which can be fastened on two horizontal transverse spars of thescaffolding, consisting of at least one rectangular bearing framecomposed of longitudinal bearing members and cross-bearing members, theends of the bearing frame are formed by the cross-bearing members andare parallel with adjacent ends of further bearing frames provided atthe same height on the scaffolding, and consisting of a bearing surfacepositioned on the bearing frame, preferably designed as a perforatedplate.

BACKGROUND OF THE INVENTION

In conventional working platforms, the respective bearing frame isequipped with a plate-shaped cover, which generally consists of alaminated plywood and is riveted to the bearing frame. The numerousperforations in the plywood, during the use of the working platform,results in time in an enlargement of the rivet bores in the plywood sothat the cover is unable to contribute to the stiffness of the workingplatform and is not given consideration during its static performancecalculation. The shifting of the cover on the bearing frame, even ifonly slightly increasing, contributes moreover to a reduction in theworkman's stepping safety during the use of the working platform.

It has therefore also already been suggested that the plywood sheets bebounded by a metallic holding frame resting on the flanges of thebearing frame, in particular when the cover at its holding frame isthereby riveted to the bearing frame by means of connecting elements.The holding frame is less subject to permanent deformation in the boresfor the connecting elements than the plywood sheets so that loosenessdue to wear in the area of these connecting elements can indeed beavoided even in the case of high stress on the working platform.However, such a working platform is expensive.

Instead it has been also known for a long time to design the bearingsurface with simple steel floors of perforated plates, which are bent attheir longitudinal sides to form short, vertical crosspiece stripsfastened to the bearing frames resting on the same. In order to achievea sufficient resistance force to rotational movement, these edgingcrosspiece strips are bent at least one more time, and as a rule severaltimes to the inside so that the bearing surface is defined on both sidesby a U-shaped to a box-shaped, more or less solid, at all positions,however, an open hollow cross section. The manufacture of such bentfootplates from bending blanks is personnel and cost intensive, and thefootplates are, because of the not closed and non-closeable hollowsections, not as torsional-resistant as desired. Furthermore, it cannotbe avoided during operation of the work platform that dirt and buildingrubble penetrates through the perforated plate into the hollow crosssections and can only be removed with great difficulty and effort.

It is also known that at least the longitudinal bearing members consistof a preferably extruded hollow section, which is approximatelyrectangular in cross section and each of which is composed of twoparallel vertical crosspieces and two horizontal flanges. Such abox-shaped design of the longitudinal bearing members results in atorsion-free design of the bearing frame, in particular, when at thecorner joints of the bearing frame the crosspieces of the cross-bearingmembers are each carried through to the outer crosspiece of thelongitudinal bearing members and are welded to the flanges and/orcrosspieces of the longitudinal bearing members. Such a corner joint hasin this manner a very robust design and can be highly stressed.Furthermore, this type of design has the advantage that the ends of thebearing frame already at its longitudinal sides form closed surfaces.

The purpose of the invention is to design a working platform of thegeneral type identified in detail above to be very reliable in operationusing simple means, and, moreover, in such a manner that the bearingsurface permanently improves the stiffness of the working platform andcan be included in the static performance calculations. Moreover, it isintended to be easy to manufacture and to be easily connectable to thebearing frame. At the same time care is taken to safely prevent anaccumulation of dirt and building rubble in the working platform.Furthermore, an arrangement is possible such that several workingplatforms are reciprocally sufficiently locked when they are storedstacked one on top of the other.

SUMMARY OF THE INVENTION

The purpose is attained according to the invention in such a manner thatat least the longitudinal bearing members each have of a closed hollowsection, which is approximately rectangular in cross section, and eachof which is composed of two parallel vertical crosspieces and horizontalflanges. Furthermore, a footplate, on which a worker can walk and whichhas the bearing surface, is clamped between the longitudinal bearingmembers. The footplate is fastened directly to the longitudinal bearingmembers. The footplate has U-shaped design and its upper horizontalcrosspiece plate is used as the bearing surface, and vertical flangeplates, which on both sides of the crosspiece plate are bentapproximately at a right angle downwardly, are fastened on the innercrosspieces of the longitudinal bearing members.

The connecting of a bearing frame, which is formed at least partiallyout of closed hollow sections, to a footplate, which is bent at bothsides each at a right angle and which does not require any further covermember, results in an extraordinarily torsion-resistant construction,however, which is constructed with little expense and can yet bedesigned very light.

It is advantageous when the footplate is designed at least partially asa perforated plate. Even though it cannot be avoided at a building sitethat dirt and construction particles fall through the perforated plate,they cannot accumulate in the footplate but instead continue to falltherethrough. The working platform thus remains clean.

The working platform is prepared to be easily stackable when the flangeplates are fastened to the longitudinal bearing members in such a mannerthat the crosspiece plate is arranged surface-parallel offset above theupper flanges of the longitudinal bearing members. It is particularlyadvantageous when the crosspiece plate projects approximately at halfthe width of the flange plates above the upper flanges of the bearingframe.

The working platform is designed extraordinarily torsion-resistant whenthe flange plates are welded to the inner crosspieces of thelongitudinal bearing members, for example through a series of resistancespot welds. The cross-bearing members, which are welded to thelongitudinal bearing members on the ends of the bearing frame, canthereby be designed as standing U-shaped bent sections, whereby thevertical sectional crosspiece of the respective cross-bearing memberborders the bearing frame on the end and the sectional flanges can bepositioned such that the sectional crosspiece at the same time coversthe hollow section of the respective longitudinal bearing member closingthe same. The entire surface of the end of the bearing frame is in thismanner available, for example for fastening of connecting elements, andthe hollow section of the longitudinal bearing members is also closedoff on the ends.

It is advantageous when the upper sectional flanges underpin thefootplate so that the same is supported also on the ends of the bearingframe in such a manner that bending is avoided.

Furthermore according to the invention, if the lower sectional flangesend above the lower flanges of the longitudinal bearing members, thefootplates and thus the entire working platform are then, when severalworking platforms are stacked, safely oriented within the respectivenext higher stacked working platform at least in the directiontransverse with respect to the longitudinal extent of the workingplatforms, which direction is important for a safe stacking. Such anarrangement results automatically when the cross-bearing members havethe same bearing-frame uniform height as the longitudinal bearingmembers; thus the projection above the longitudinal bearing members isat the top just as high as the insertion at the bottom above thelongitudinal bearing member lower edge.

The working platform can be fastened in a simple manner to thescaffolding when at least two hook-shaped mountings, which are fastenedto the cross-bearing members and are received on the transverse spars ofthe scaffolding, are provided on each end of the bearing frame. Adjacentworking platforms can thereby be supported with their ends closelyresting next to one another on the same transverse spar when themountings on the cross-bearing members of the bearing frame are arrangedin the direction parallel to the ends and are spaced from thelongitudinal sides of the bearing frame, which longitudinal sides areformed by the longitudinal bearing members, in such a manner that theyare offset with respect to the mountings on the adjacent cross-bearingmembers of a further similar bearing frame so that with the bearingframes being aligned the mountings can be arranged on the sametransverse spar. It is thereby advantageous when the mountings areprovided in pairs on the cross-bearing members and in the vicinity ofthe longitudinal bearing members so that the stress on the workingplatform is transferred as evenly distributed as possible onto thescaffolding. The mountings can be welded in a simple and effectivemanner to the cross-bearing members of the bearing frame.

If the working platform designed according to the invention is aparticularly long extended part, it may be advantageous for thestiffness of the working platform when at least one reinforcing bar isclamped between the longitudinal bearing members on the bearing frameparallel to the cross-bearing members, advantageously approximately inthe center between the cross-bearing members which are on both ends.

The invention reduces the building components needed for a workingplatform to very few in number, simply designed and therefore alsoinexpensively manufacturable building elements, which, however, as awhole with a light-weight construction throughout permit a veryinherently stable and highly stressable working platform.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be discussed in greater detail hereinafter inconnection with one exemplary embodiment and the drawings, in which:

FIG. 1 is a top view of the working platform of the invention,

FIG. 2 is a front view in the cross section along B--B of FIG. 1, inwhich the working platform is illustrated in its position of use,

FIG. 3 is a cross sectional view along A--A of FIG. 1,

FIG. 4 shows an enlarged detail C of FIG. 3,

FIG. 5 shows an enlarged detail D of FIG. 1,

FIG. 6 is the enlarged front view of FIG. 2,

FIG. 7 is the front view of FIG. 6, however, not in cross section, and

FIG. 8 shows several working platforms stacked one on top of the othercorresponding to FIG. 6.

The same component parts on an adjacent working platform are indicatedwith reference numerals primed, however, are not shown in the drawings.

A working platform according to the invention consists, corresponding toFIGS. 1 to 3, essentially of a bearing frame 1, a footplate 2 andhook-shaped mountings 3.

The bearing frame 1 is composed of two longitudinal bearing members 11and two cross-bearing members 12, which are welded together at thecorners 13 of the bearing frame 1. A reinforcing bar 14 is clampedbetween the longitudinal bearing members 11 approximately centeredbetween the cross-bearing members 12 and is connected therebetween withits own material or also by welding seams. The cross-bearing members 12form surfaces on the bearing frame 1, which surfaces are closed on theend of the frame and to which the mountings 3 are welded in such amanner that the hook 31 provided thereon opens downwardly in theposition of use so that the hook eyelets 32 of each end 1a of thebearing frame can cover a transverse spar of the scaffolding.

The footplate 2 is designed, in accordance with FIG. 1, as a perforatedplate and is clamped between the longitudinal bearing members 11 justlike the reinforcing bar 14. FIG. 3 shows resistance spot welds 4between the bearing frame 1 and the footplate 2, with which flangeplates 21 of the footplate 2, which are vertical in the position of use,are connected with a rigid substance to the longitudinal bearing members11. These longitudinal bearing members 11 are designed each as anupright positioned rectangular, extruded hollow cross section 110, whichaccording to FIG. 6 is composed of horizontal upper and lower flanges11a, 11b and inner and outer crosspieces 11c, 11d.

The profile of one of the cross-bearing members 12 and its relativeposition on the longitudinal bearing members 11 can be easily recognizedin FIG. 4; it has a U-shape and is composed of a sectional crosspiecel2a and upper and lower sectional flanges 12b, 12c bent from thesectional crosspiece 12a. The cross-bearing member 12 is clamped betweenthe longitudinal bearing members 11 in such a manner that its uppersectional flange 12b projects above the upper flange 11a of thelongitudinal bearing member at a height h₁ (FIG. 6). The thus formedprojecting space 12d in the width of the longitudinal bearing members 11are disengaged from the crossbars 12.

The lower sectional flanges 12c are, on the other hand corresponding toFIG. 4, inserted at a height h₂ above the lower flanges 11b of thelongitudinal bearing members 11 into the bearing frame 1. The height h₁is at most as great as the height h₂ so that (FIG. 8) working platforms,which are placed one on top of the other can be easily and securelystacked. If the heights h₁ and h₂ are the same, then the cross-bearingmembers 12 have also the bearing-frame uniform height H the same as theheight of the longitudinal bearing members 11.

The mountings 3 are, with reference to the cross-bearing members 12, notprovided mirror inverted on the bearing frame 1, but they are insteadoffset in pairs on its two ends 1a so that adjacent bearing frames 1, 1'can be placed on the same transverse spar of a scaffolding, however,their longitudinal sides 1b are still flush. This situation can beeasily recognized in FIG. 7 because the not visible mountings 3 are alsopositioned on the end 1a, which lies behind the drawing plane. Themountings 3 are welded therearound to the sectional crosspieces 12a andare provided in one piece in a suitable manner with a bracket plate 33(FIG. 5).

The footplate 2 is also designed in a U-shape (FIG. 6). A crosspieceplate 22 is thereby provided between the flange plates 21. The upperside 22a of the crosspiece plate, which upper side is horizontal in theposition of use, forms the bearing surface 20 (FIG. 1). Its bottom side22b rests on the upper sectional flanges 12b of the cross-bearingmembers 12, whereas the part of the flange plate 21 extending into thebearing frame 1 is connected to the inner crosspieces 11c of thelongitudinal bearing members 11 adjacently resting flat thereagainst, inthe easiest manner as already mentioned above, by means of resistancespot weldings 4.

A possibly provided reinforcing bar 14 is instead welded best by meansof a throat seam to the longitudinal bearing member 11.

LIST OF REFERENCE NUMERALS

1 Bearing frame

1' Bearing frame, adjacent

1a End

1a End, adjacent

1b Longitudinal side

11 Longitudinal bearing member

110 Hollow section

11a (Upper) flange

11b (Lower) flange

11c (Inner) crosspiece

11d (Outer) crosspiece

12 Cross-bearing member

12' Cross-bearing member, adjacent

12a Sectional crosspiece

12b (Upper) sectional flange

12c (Lower) sectional flange

12d Spaces

13 Corner

14 Reinforcing bar

2 Footplate

20 Bearing surface

21 Flange plate

22 Crosspiece plate

22a (Upper) side

22b (Lower) side

3 Mounting

3' Mounting, adjacent

31 Hook

32 Hook eyelet

33 Bracket plate

4 Resistance spot weldments

h₁ Height of upper sectional flange, width

h₂ Height of lower sectional flange

H Height (longitudinal bearing and cross-bearing members)

I claim:
 1. A working platform for a scaffolding, the platform beingfastenable on two horizontal transverse spars of the scaffolding,comprising: at least one rectangular bearing frame composed oflongitudinal bearing members and cross-bearing members, ends of theframe being formed by the cross-bearing members and being parallel witheach adjacent end of further bearing frames supportable at the sameheight on the scaffolding, and a footplate secured on the longitudinalbearing members of the bearing frame, the footplate defining a bearingsurface which is adapted to support a person, the footplate beinginverted U-shaped and having an upper horizontal crosspiece platedefining the bearing surface and having vertical flange platesdownwardly bent respectively on both sides of the crosspiece plate, thelongitudinal bearing members each comprising a closed hollow section,which is approximately rectangular in cross section, and which comprisestwo parallel vertical pieces and horizontal flanges, and the flangeplates being fastened onto an inner one of the vertical pieces so thatthe crosspiece plate is vertically offset above and parallel an upperone of the flanges, the cross-bearing members and the longitudinalbearing members having a same height dimension and the cross bearingmembers being offset above the longitudinal bearing members, and atleast two hook-shaped mountings being provided on each of thecross-bearing members, the at least two hook-shaped mountings beingadapted for receiving the transverse spars of the scaffolding therein.2. The working platform according to claim 1, wherein the footplate isat least a partially perforated plate.
 3. The working platform accordingto claim 1, wherein the crosspiece plate is positioned at approximatelyhalf of the height of the flange plates above an upper one of theflanges.
 4. The working platform according to claim 1, wherein theflange plates are welded respectively to inner ones of the verticalpieces of the longitudinal bearing members.
 5. The working platformaccording to claim 1, wherein the cross-bearing members are welded tothe longitudinal bearing members on an end of the bearing frame, thecross-bearing members are C-shaped bent sections opening sidewardly, avertically extending bight of the respective cross-bearing memberborders the end of the bearing frame, and the flanges of the respectivecross-bearing member are positioned such that the vertically extendingbight covers and closes the hollow section of the respectivelongitudinal bearing member.
 6. The working platform according to claim5, wherein an upper one of the flanges of the cross-bearing memberunderpin the footplate.
 7. The working platform according to claim 5,wherein a lower one of the flanges of the cross-bearing member end abovethe lower horizontal flanges of the longitudinal bearing members.
 8. Theworking platform according to claim 1, wherein the mountings arearranged on the cross-bearing members of the bearing frame and arespaced from longitudinal sides of the bearing frame, the longitudinalsides being formed by the longitudinal bearing members, the mountingsbeing offset with respect to the longitudinal bearing members on anadjacent cross-bearing member of a further bearing frame so that withthe bearing frames are aligned and the mountings of each bearing frameare arranged on the same transverse spar.
 9. The working platformaccording to claim 8, wherein the mountings are provided in pairs on thecross-bearing members and near the longitudinal bearing members.
 10. Theworking platform according to claim 1, wherein the mountings are weldedto the cross-bearing members of the bearing frame.
 11. The workingplatform according to claim 1, wherein at least one reinforcing bar isclamped between the longitudinal bearing members on the bearing frame,the at least one reinforcing bar being parallel to the cross-bearingmembers.
 12. The working platform according to claim 1, wherein saidbearing surface is a perforated plate.
 13. A scaffolding platformincluding two platform units each having one end mounted on a singlescaffolding spar, each platform unit extending in first and seconddirections, the first direction being generally transverse to the seconddirection, each platform unit comprising:two elongate side bearingmembers spaced from each other in the second direction and extending inthe first direction, the side bearing members each having inner andouter vertical pieces, and upper and lower horizontal flanges, thepieces and flanges of each side bearing member enclosing a hollowinterior which is open at each end, the upper horizontal flangesextending in a plane; two elongate end bearing members respectivelyconnected at the ends of the side bearing members and extending in thesecond direction joining the two side bearing members, the end bearingmembers each having a C-shape including horizontal upper and lowerplates, and a vertical outer bight extending between the upper and lowerplates, the upper plate extending vertically offset above the plane ofthe upper horizontal flanges; an inverted U-shaped plate providing aperson supporting surface, the plate having a horizontal crosspiece andflange members extending downwardly from the two sides of the horizontalcrosspiece, the flange members being respectively secured to the innervertical pieces of the side bearing members, the horizontal crosspiecebeing parallel to the plane and vertically offset above the plane; andat least two hook-shaped mountings fastened on each of the end bearingmembers, the hook-shaped mountings being adapted to be received on thetransverse scaffolding spars to support the platform units therefrom,the hook-shaped mountings extending in the first direction, thehook-shaped mountings being respectively offset inwardly in the seconddirection from the ends of the side bearing members so that adjacentplatforms are supported by the single scaffolding spar and have the sidebearing members of the two platform units aligned.